1. Field of the Invention
The present invention relates generally to imaging apparatuses, and more particularly to a method for dissipating heat produced in a scan head assembly of an imaging apparatus.
2. Description of the Related Art
Imaging apparatuses, such as document scanners, are widely used for scanning printed media sheets and generating a digital image thereof. A conventional imaging apparatus includes a flatbed enclosure having a transparent board disposed on an open top end of the flatbed enclosure, and a scan head assembly disposed within the flatbed enclosure. The scan head assembly comprises a lamp, a plurality of mirrors, a plurality of lenses and a Charge Coupled Device (CCD). For carrying out scanning of a media sheet, the media sheet is placed on the transparent board in a manner such that a surface of the media sheet, which is to be scanned, is in contact with the transparent board. Thereafter, the lamp is utilized to illuminate the surface of the media sheet that is to be scanned. The plurality of mirrors and the plurality of lenses direct a light reflected from a portion of the surface of the media sheet onto the CCD. The CCD is adapted to generate an electronic image data of the surface of the media sheet from the light reflected therefrom. A typical scan head assembly may be moved along a length of the media sheet for scanning the entire media sheet and generating an electronic image data thereof.
For high speed scanning of a large number of media sheets, conventional imaging apparatus utilizes an automatic document feeder (ADF) assembly that is configured in an operative coupling with the scan head assembly of the conventional imaging apparatus. Such imaging apparatus may be preferably referred to as “ADF scanner”. The ADF assembly of a typical ADF scanner is utilized to receive a plurality of media sheets for carrying out scanning thereof at high speed. More specifically, the ADF assembly includes a tray for receiving the plurality of media sheets and an associated media sheet moving mechanism that enables the scanning of the plurality of media sheets. In a typical ADF scanner, the media sheets are scanned by moving the media sheets over the scan head assembly one at a time such that the scan head assembly illuminates each of the media sheets and generates an electronic image data thereof More specifically, in the typical ADF scanner, the scan head assembly is stationary while the ADF assembly moves the media sheets received in the tray over the scan head assembly, in a manner such that one media sheet is moved over the scan head assembly at a time. Generally, the ADF assembly of the ADF scanner may receive a large number of media sheets, which may be scanned at a very high speed, for example at a speed of about 70 sheets per minute.
The high speed scanning enables a large number of media sheets to be scanned in a short span of time with minimum human involvement, thereby providing a cost-effective and less time-consuming solution for carrying out bulk scanning works. A typical high speed scanning requires more light to process images of the media sheets, which in turn requires more illumination of the media sheets for effective scanning. More illumination of the media sheets requires operating the lamp at a higher power, which leads to generation of more heat. Therefore, during the high speed scanning, there may result a temperature rise within the flatbed enclosure due to generation of more heat by the lamp. Further, a conventional flatbed enclosure is generally sealed to prevent entry of contaminants into the flatbed enclosures and accordingly, the heat produced within the flatbed enclosures may not be easily dissipated therefrom, thereby leading to a further rise in the temperature. A rise in temperature within the flatbed enclosure may result in rise in temperature of the scan head assembly. The working efficiency of the scan head assembly may be affected due to high temperature thereof, thereby resulting in decreased quality of scanning of the media sheets. Moreover, a prolonged exposure of the scan head assembly to a high temperature may result in shortening of life span thereof.
The flatbed enclosures may be provided with additional cooling mechanisms, such as cooling fins, cooling fans, and the like to enable the scan head assembly to dissipate heat. However, inclusion of additional cooling mechanisms may require the flatbed enclosures to be redesigned to accommodate the cooling mechanisms. Further, such cooling mechanisms need to be designed in a manner such that the cooling mechanisms adequately block the entry of contaminants into the flatbed enclosures. Moreover, inclusion of such cooling mechanisms may not be cost-effective and may increase an overall operating and maintenance cost of the imaging apparatus.
Accordingly, there persists a need to dissipate heat produced in a scan head assembly of an imaging apparatus, which overcomes the drawbacks and limitations of prior art imaging apparatuses. More specifically, there persists a need to dissipate heat produced in a scan head assembly of an imaging apparatus in a manner that precludes inclusion of additional cooling mechanisms in a flatbed enclosure of the imaging apparatus. Moreover, there persists a need to dissipate heat produced in a scan head assembly of an imaging apparatus in an easy, reliable and cost-effective manner.